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Steam heater

Today when I turned on the heat my steam boiler did something weird. Downstairs in the basement steam was blowing out of one of my pipes. The pipe is coming out of the top of the furnace and it goes 3/4 ways to the ground were it is cut off. Now I noticed when i flip the switch up top it lets steam out of this pipe. Also it says max PSI is 15. when I restarted it and waited once it got to 15psi it went off again. Is the unit over heating? Or is this normal?

Could anyone tell me if I have to worry about this and what to do to fix it if anything. Thanks


  • jim s_2
    jim s_2 Member Posts: 112
    Pressure relief valve

    Set to open at 15 psi on steam boilers,it should not be doing what it`s doing under normal operating conditions.

    You might have an improperly set or defective pressuretrol or the relief valve itself is defective,you might want to call a pro .
  • Jamie Hall
    Jamie Hall Member Posts: 21,541
    Not normal!!! TURN IT OFF!!!

    Be happy that your pressure relief valve is working properly, because something else most assuredly isn't.  A residential boiler should never, ever go over a few psi (most fittings, valves, etc., are rated around 3 psi, with a never exceed of 10).

    TURN OFF THAT BOILER NOW, with the emergency switch, and get a pro in there, pronto, to find out what's wrong.  I do not want to sound alarmist, but if that safety valve happened to stick shut, what you have could launch your whole house into low orbit.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Freefalling
    Freefalling Member Posts: 2
    Steam heat

    Thanks, its been off since it did it the second time and I watched it. I will have to call someone Monday, I suppose to get it looked at
  • You need a Pro!

    Jim S and Jamie's advice is right on. You have a serious safety issue. Call a pro to look at it. If it is what i think it is it's a simple fix.

     I read this post  and was thinking you might want to get Dan's book "We Got Steam Heat!. it's available on this site  Here's the link:


    It's written for the homeowner, is humorous, and is easy to understand.  After  an evening or two of reading you'll know a lot more about your steam system.  For most people the knowledge learned from this book has saved them many times its value.
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